All electrical connections in a flammable leakage zone should be sealed. In the case of a splice, sealed splices should be used.

SWPM 20-30-12 paragraphs 7.B or 7.C (for temperature A and B zones) or paragraphs 8.B or 8.C (for high temperature zones C and D) are the preferred methods. Although there are sealed splice kits with heat shrink sleeves, use of a heat gun in a flammable leakage zone is not recommended.

Tapes used in the previously mentioned SWPM tasks do use P-421, which is a temperature grade D tape and can be used for all temperature repairs.